Novel Transgenic Mouse Model of Polycystic Kidney Disease

Transmembrane protein 207 (TMEM207) is characterized as an important molecule for invasiveness of gastric signet-ring cell carcinoma cells. To clarify the pathobiological effects of TMEM207, we generated 13 transgenic mouse strains, designated C57BL/6-transgenic (Tg) (ITF-TMEM207), where the mouse Tmem207 is ectopically expressed under the proximal promoter of the murine intestinal trefoil factor gene. A C57BL/6-Tg (ITF-TMEM207) mouse strain unexpectedly exhibited a high incidence of spontaneous kidney cysts with histopathological features resembling human polycystic kidney disease, which were found in approximately all mice within 1 year. TMEM207 immunoreactivity was found in noncystic kidney tubules and in renal cysts of the transgenic mice. The ITF-TMEM207 construct was inserted into Mitf at chromosome 6. Cystic kidney was not observed in other C57BL/6-Tg (ITF-TMEM207) transgenic mouse strains. Although several genetically manipulated animal models exist, this mouse strain harboring a genetic mutation in Mitf and overexpression of Tmem207 protein was not reported as a model of polycystic kidney disease until now. This study demonstrates that the C57BL/6-Tg (ITF-TMEM207) mouse may be a suitable model for understanding human polycystic kidney disease.